The detection of trace pollutants has become increasingly important. The currently available measurement techniques for most toxic chemicals are quite complicated and requires skilled operators. The whole procedure is usually expensive, lengthy and not practical for field analysis. We propose to develop and commercialize enzyme sensors for toxic chemicals in which detection is based on inhibition of the enzyme. The enzyme inhibition technique can be used for detection of a variety toxic substances including heavy metals such as lead. Federal health officials describe lead poisoning as the most common and societally devastating environmental disease facing American children. The specific objective of this project is to develop new sensors and procedures for the analysis of lead in blood consistent with the downward revision of the action level of lead in the blood of children. The CDC holds that the development of this test is necessary to meet the mission to eliminate lead poisoning in the United States. The researchers submitting this proposal have collaborated successfully to develop prototype enzyme-based sensors which will be a crucial background for the research and development described in this proposal. Successful sensors for use in detecting lead in blood have huge commercial potential